Expansion engine

ABSTRACT

An expansion engine having a motor driven by combustion gases delivered by a combustion apparatus and a control unit for the motor. The motor includes an epicycloidal piston rotatably mounted in a cylinder, an expansion chamber, an air compression chamber, an inlet for fresh air and an outlet for the exhaust gases. The control unit has an epicycloidal piston rotatably mounted in a cylinder, an inlet chamber for the combustion gases provided with an inlet channel for the combustion gases with the inlet channel being in open connection with the combustion apparatus and an air compression chamber provided with an outlet channel connected with the combustion apparatus and provided with a non-return valve. The inlet chamber and the air compression chamber of the control unit are connected by channels with the expansion chamber and the compression chamber, respectively of the motor.

United States Patent 1 Hubers EXPANSION ENGINE [76] Inventor: CornelisHubers, Van Ostadelam 2,

Rozenburg, Netherlands [22] Filed: Oct. 29, 1971 21 Appl. No.: 193,685

[30] Foreign Application Priority Data Primary ExaminerClarence R.Gordon y-599mm D vi M e Ma her [451 Jan. 8, 1974 [5 7] ABSTRACT Anexpansion engine having a motor driven by combustion gases delivered bya combustion apparatus and a control unit for the motor. The motorincludes an epicycloidal piston rotatably mounted in a cylinder, anexpansion chamber, an air compression chamber, an inlet for fresh airand an outlet for the exhaust gases. The control unit has anepicycloidal piston rotatably mounted in a cylinder, an inlet chamberfor the combustion gases provided with an inlet channel for thecombustion gases with the inlet channel being in open connection withthe combustion apparatus and an air compression chamber provided with anoutlet channel connected with the combustion apparatus and provided witha non-return valve. The inlet chamber and the air compression chamber ofthe control unit are connected by channels with the expansion chamberand the compression chamber, respectively of the motor.

2 Claims, 3 Drawing Figures EXPANSION ENGINE This invention relates toan expansion engine for or combined with a combustion apparatus whichsupplies a mixture of combustion gases under pressure, said expansionengine being characterized in that the expansion engine is constructedas a rotary piston driving engine with an epicycloidal rotary piston,comprising a control means which is likewise constructed as a rotarypiston means with an epicycloidal rotary piston, both the housing of therotary piston driving engine and the housing of the control meanscomprising two inlet openings and two outlet openings, at least theoutlet of the control means being provided with a valve, preferably anon-return valve. In consequence of the fact that in the case of theexpansion engine according to the invention the combustion takes placeoutside said engine in a separate combustion chamber, said combustionmay be controlled such that it is substantially complete. The control ofthe expansion engine according to the invention is particularly simplein that the control means is constructed as a rotary piston means with aepicycloidal rotary piston. This entails the advantage that only valvesor closing means need be provided in the conduits or channels throughwhich air passes. Said valves may preferably be of the non-return valvetype.

According to a preferred simple embodiment of the expansion engineaccording to the invention the rotary pistons of the motor and thecontrol means may be triangular epicycloidal pistons, thecompressionoutlet of the rotary piston motor being directly connected tothe compression chamber of the control means the outlet of whichcommunicates via a non-return valve with the combustion apparatus.

In order to increase the efficiency of the expansion engine according tothe invention the compression outlet of the rotary piston motor may beconnected via a conduit comprising a non-return valve with a coolerwhich communicates with the compression chamber of the control means.

The expansion engine according to the invention may also be of amulti-stage construction, the outlet of the expansion chamber of thefirst stage being in open communication with the expansion chamber ofthe next stage, the compression chamber of said next stage communicatingvia a non-return valve with a cooling chamber with buffer action, saidcooling chamber being inopen communication with the compression chamberof the preceding stage which via a non-return valve communicates withthe combustion apparatus.

If desired the compression chamber of the preceding stage maycommunicate via a non-return valve with a second cooling chamber withbuffer action, which is in open communication with the control means. Inthis way an additional increase of the efficiency can be attained.

The invention will be further explained below with reference to thedrawings showing diagrammatically and by way of example two embodimentsof the expansion engine according to the invention.

The drawings show in FIG. 1 a cross-section of a single stage embodimentof the ex-pansion engine according to the invention;

FIG. 2 a cross-section of a two-stage embodiment,

and a FIG. 3 a side view from left multi-stage embodiment.

to right in FIG. 2 of said The rotary piston engine shown in FIG. 1comprises a housing 1 in which a triangular epicycloidal piston 2 canrotate clockwise. The housing 1 comprises an air inlet opening 3, an airoutlet opening 4 for the expanded combustion gases, an air outletopening forthe air compressed in a chamber 6 of the housing I by therotary piston 2 and an inlet opening or channel 7 for supplying hotcombustion gases under pressure to a chamber 8 in which said combustiongases expand. The outlet opening 5 and the inlet opening 7 are separatedfrom each other via a portion 9 against which the piston 2 sealinglyabuts.

The outlet opening 5 and the inlet opening v7 are controlled by acontrolmeans 10 which is embodied as a rotary piston means with anepicycloidal rotary piston 11, the housing of said rotary piston meansbeing integral with the housing 1 of the expansion engine. In aseparating wall 12 which separates the rotary piston chamber of theexpansion engine from the rotary piston chamber of the control means 10there are provided the outlet opening 5 and the inlet opening 7. Thehousing 1 furthermore comprises an inlet opening 13 for the combustiongases opening into the chamber of the rotary piston 11 of the controlmeans 10, said combustion gases arriving under pressure from acombustion apparatus (not shown), said inlet opening being in opencommunication with said combustion apparatus. The housing 1 furthermorecomprises an inlet to the combustion chamber opening 14 whichcommunicates via a valve means (not shown), for example a non-returnvalve, with the combustion apparatus (not shown).

Theinstallation described above operates as follows: The combustiongases produced in the combustion apparatus (not shown) enter via opening13 the control means 10 and are conveyed by the rotary piston 11 of thecontrol means 10 via the inlet opening 7 in the separating wall into anexpansion chamber 8 formed by the rotary piston 2 and the housing 1 ofthe expansion engine. These combustion gases expand in said chamber anddrive the rotary piston 2. When the rotary piston 2 has rotated so farthat the outlet 4 comes into communication with the atmosphere, theexpanded combustion gases escape into'the atmosphere. Meanwhile therotary piston 2 has been rotated so far that the air inlet opening 3 isreleased and the chamber 6, which during rotation becomes steadilylarger, has filled itself with air. When the rotary piston 2 continuesits rotation, the air inlet opening 3 is closed whereupon the aircontained in the chamber 6 iscompressed until the air outlet opening 5is released and the air compressed in the chamber 6 flows into a chamberbetween the rotary piston 11 and the housing 1 of the control means 10.The chamber 6 is thereby continuously reduced and the air containedtherein is thereby compressed, said air being displaced in front of therotary piston 2. The rotary piston 11 displaces itself according to thesame angle as the rotary piston 2 in the same sense of rotation so thatconsequently between the rotary piston 11 and the housing of the controlmeans 10 a chamber is formed into which the compressed air is driven bythe rotary piston 2 via the air outlet opening 5. When the rotary piston11 has rotated so far that the air outlet opening 14 is released, saidair is driven by the rotary piston 11 into the combustion apparatus.Meanwhile, however a second quantity of combustion gases has beensupplied to the rotary piston 2, expanded and released to theatmosphere, while a second quantity of air is compressed and a thirdquantity of combustion gases is pressed via the inlet opening 7 by therotary piston 11 of the control means into a chamber between the rotarypiston 2 and the housing 1. The afore-described cycle repeats itselftherefore three times at each revolution of the rotary pistons 2 and 11.

The expansion engine shown in FIGS. 2 and 3 differs from the oneaccording to FIG. 1 in that it is of the three-stage type. In thisengine the cylinder 15 of the third stage comprises a valveless airinlet 16 opening into a chamber 17 in which the air entered therein issubjected to a first compression. The compressed air flows via an airoutlet 19 provided with a non-return valve 18 via a conduit 20 to thefirst intermediate cooler 21 which is cooled with the aid of a coolingdevice (not shown). From said intermediate cooler 21 the cooledcompressed air flows via a conduit 22 to a valveless air inlet 23 into achamber 24 of the second cylinder 25 of the second stage, in which theair is subjected to a second compression. Said compressed air flows viaan air outlet 27 comprising a non-return valve of said second cylindervia a conduit 28 to a second cooler 29 which is likewise cooled with theaid ofa cooling device (not shown). From said second cooler 29 the airflows via a conduit 30 and the air inlet 31 of the cylinder 32 of thefirst stage into the chamber 33 of said cylinder in which said air issubjected to a third compression. The air which has been compressed inthis way goes via an air outlet 35 provided with a non-return valve 34to a combustion apparatus from which the combustion gases producedtherein flow via a valveless inlet 36 into the filling chamber 37 of thecylinder 32 and drive the piston 38 of said cylinder. The cylinder 32 isprovided with a valveless outlet 39 communicating with a chamber 40 ofthe second cylinder 25 in which chamber the combustion gases expand forthe second time thereby driving the piston 41 of the second cylinder 25,said piston rotating in a sense contrary to the sense of rotation of thepiston 38 of the first cylinder. The second cylinder 25 is connected viaa channel 42 to a chamber 43 of the third cylinder 15, in which chamberthe combustion gases expand for the third time thereby driving thepiston 44 of said third cylinder which rotates in the same sense ofrotation as the piston 38 of the first cylinder. The cylinder 15 of thethird stage comprises a valveless outlet 45 through which the combustiongases flow into the atmosphere.

In the above-described instance the first stage 32, also serves as acontrol device. If the first stage 32 is used exclusively as anoperating device the intermediate cooler 29 is cancelled. It is obviousthat in that case the assembly operates as a two-stage engine. The thirdstage then serving as an operating device should then be provided in thesame manner as the operating device 10 in FIG. 1.

It is obvious that the invention is not restricted to the embodimentsdescribed above by way of example but that many modifications may bemade therein without departing from the scope of the invention, as laiddown in 'the claims. It is, for example, also possible to supply alreadycompressed air to the air inlet opening 3. For starting a normal startermotor may be used. However, it is also possible to use a reservoir withpressurized air for starting the motor, said reservoir being adapted tobe charged again by the motor. One may also operate with an intermediatecharging, and instead of nonreturn valves also controlled valves may beused.

What I claim is:

1. An expansion engine having a motor comprising an epicycloidal pistonrotatably mounted in a cylinder and driven by combustion gases deliveredby a combustion apparatus comprising a continuously operating burnerarranged in a housing and having an expansion chamber and an aircompression chamber said engine comprising control means for said motor,said control means having an epicycloidal piston rotatably mounted in acylinder, the first mentioned piston and cylinder being larger than thesecond mentioned cylinder and piston, said control means having an inletchamber for the combustion gases provided with an inlet channel for saidcombustion gases, said inlet channel being in open connection with thecombustion apparatus, said control means having also an air compressionchamber provided with an outlet channel connected with said combustionapparatus and provided with a non-return valve, said inlet chamber ofthe control means being connected by a channel with the expansionchamber of the motor, the air compression chamber of said control meansbeing connected by a channel with the air compression chamber of themotor, said motor being provided with an inlet for fresh air and anoutlet for the exhaust gases.

2. An expansion engine according to claim 1, characterized in that it isof a multi-stage construction, the outlet of the expansion chambers ofeach two adjacent motors are in open communication with one another, theair compression chambers of each two adjacent motors with exception ofthe air compression chamber of the first motor, being connected via acooling chamber with one another, the outlet of each compression bustionapparatus.

1. An expansion engine having a motor comprising an epicycloidal pistonrotatably mounted in a cylinder and driven by combustion gases deliveredby a combustion apparatus comprising a continuously operating burnerarranged in a housIng and having an expansion chamber and an aircompression chamber said engine comprising control means for said motor,said control means having an epicycloidal piston rotatably mounted in acylinder, the first mentioned piston and cylinder being larger than thesecond mentioned cylinder and piston, said control means having an inletchamber for the combustion gases provided with an inlet channel for saidcombustion gases, said inlet channel being in open connection with thecombustion apparatus, said control means having also an air compressionchamber provided with an outlet channel connected with said combustionapparatus and provided with a non-return valve, said inlet chamber ofthe control means being connected by a channel with the expansionchamber of the motor, the air compression chamber of said control meansbeing connected by a channel with the air compression chamber of themotor, said motor being provided with an inlet for fresh air and anoutlet for the exhaust gases.
 2. An expansion engine according to claim1, characterized in that it is of a multi-stage construction, the outletof the expansion chambers of each two adjacent motors are in opencommunication with one another, the air compression chambers of each twoadjacent motors with exception of the air compression chamber of thefirst motor, being connected via a cooling chamber with one another, theoutlet of each compression chamber being provided with a non-returnvalve, the outlet of the compression chamber of said first motor beingconnected via its non-return valve with the combustion apparatus.